Whisk flour, sugar, baking powder, baking soda, and salt in a large bowl until no leavening lumps remain.
Whisk buttermilk, eggs, melted butter, and vanilla in a second bowl until smooth.
Fold wet mixture into dry just until flour streaks disappear, leaving small lumps. Rest batter 10 minutes.
Heat griddle over medium-low to 350°F; wipe with half the oil. A batter drop should sizzle gently without smoking.
Pour scant 1/3-cup portions onto griddle. Cook 2 to 3 minutes until bubbles stay open and edges look dry.
Flip once; cook 1 to 2 minutes until underside is golden and center springs back. Re-oil griddle as needed.